Erythrocytes undergoing steady shear flow at low stresses lose hemoglobin when they interact with solid surfaces, as occurs in artificial organs and implants designed to handle blood. The mechanism of this type of hemolysis is not understood, but abundant evidence indicates that both blood chemistry and solid-surface character influence its extent. We propose here to employ the extensive resources of two campus laboratories (both engaged previously in hemolysis research) to investigate the role of several variables: erythrocyte deformability, membrane strength, plasma components such as proteins and additives described herein, material surface chemistry and roughness. Shearing tests will be performed in a rotating disk apparatus whose disk surfaces are fabricated from desired materials, and plasma hemoglobn levels sampled at intervals to generate the kinetic hemolosys curve. Blood will be extensively characterized before and after shearing, with cell deformability examined by resistive pulse spectroscopy. Morphology of cells and disk surfaces will be viewed with optical and scanning electron microscopy, including cases wherein cells attached to the surfaces are fixed while hemolyzing. Preliminary results concerning polynucleic acid additives, and RPS data indicating that shear flow may improve the mechanical condition of erythrocytes, are particularly intriguing. While basic mechanisms of hemolosys are sought, applications to the technology of blood stroage and manipulation, and biomaterials design, also arise.